catalog.py fail to untar on Python 2.6

[mvieno]

[emep4uk@nemesis Common_4.17]$ ./catalog.py -R rv4_17
Queue download:   2.7G rv4_17input
Queue download:  21.1G meteo2015
Queue download: 715.7K rv4_17source
Queue download: 524.7K rv4_17docs
Queue download:   2.3G rv4_17output
Queue download:  26.1G Total
Do you wish to proceed? [Y]/n:Y
Untar    meteo2015        1.8G EMEP_MSC-W_model.rv4.17.OpenSource/meteo2015/EECCA/meteo201507.tar.bz2
Traceback (most recent call last):
  File "./catalog.py", line 517, in <module>
    main(parse_arguments()[0])
  File "./catalog.py", line 512, in main
    x.unpack(opts.verbose, opts.ask)
  File "./catalog.py", line 330, in unpack
    with tarfile.open(self.dst, 'r') as infile:
AttributeError: 'TarFile' object has no attribute '__exit__'

[cskarby]

https://github.com/metno/emep-ctm/blob/3578f91ae88362980962d868bceeedd2cdc38763/catalog.py#L330

[cskarby]

The user uses Python version earlier than 2.7, which added support for the "context manager" protocol (which is necessary for using the with statement) to the tarfile module. See https://stackoverflow.com/questions/6086603/statement-with-and-tarfile

[mvieno]

My workaround is to remove the "unpack" call in the catalog.py at the end of the python script

[avaldebe]

@mvieno Do you have Python 2.7 or later at your HPC? Maybe trough a module load?

[avaldebe]

I know that a download link would be easier, but the EMEP01 meteorology files hare so big that they need to be downloaded individually...

If you do not have Python 2.7, I'll look into untaring without with.

Also, the 2015 EECCA meteorology on this release is the same that on the previous release. So if you already have it, you do not need to download it again.

[mvieno]

Hi. Possibly, but instead of doing that I changed the python script skipping the automatic untar. I actually prefer untar and unzip manually. I've now also added the python2.7.

[avaldebe]

@mvieno I'm glad you found a solution and that you moved to Python 2.7. Python 2.6 reached end of life on 2013 and 2.7 will stay until 2020. I just committed a fix for Python 2.6, but considering how outdated it is I do not think that we should support it any longer.